1. Field of the Invention
The present invention relates to power conversion circuits and systems. More specifically, the present invention relates to DC to DC converters.
While the present invention is described herein with reference to illustrative embodiments for particular applications, it should be understood that the invention is not limited thereto. Those having ordinary skill in the art and access to the teachings provided herein will recognize additional modifications, applications, and embodiments within the scope thereof and additional fields in which the present invention would be of significant utility.
2. Description of the Related Art
DC to DC converters are known in the art. DC to DC converters function to efficiently change a DC voltage from one level to another. This conversion is typically accomplished with switching mode power transistors which convert an input DC voltage to an AC square wave and then convert the AC square wave to a higher or lower voltage amplitude via the turns ratio transformation of a power transformer. The transformer output square wave is then rectified and filtered to generate the new DC voltage level at higher or lower voltage relative to a different ground reference than the input DC voltage power level.
DC to DC converters are often used to provide regulated power for electronic and electrical systems from a source of unregulated power. A variety of DC to DC converters are known in the art including buck, boost and buck-boost converters. See "Two-Inductor Boost and Buck Converters" by J. L. White and W. J. Muldoon published in the IEEE 18th Annual Power Electronics Specialists Conference June 21-26, 1987.
Boost type DC to DC converters are particularly useful. Boost type DC to DC converters convert an input direct current (DC) signal at a first lower voltage to an output DC voltage at a second higher voltage level.
Coupled inductor type boost DC to DC converters utilize an inductor to provide DC level shifting. Coupled inductor type boost DC to DC converters are widely used due to the inherent ripple current reduction capability of the inductive component. However, conventional coupled inductor type boost DC to DC converters typically utilize at least three separate magnetic components for providing the functions of energy storage, power switch drive, input current ripple cancellation and regulated low voltage supply generation. The weight, size and cost associated with multiple magnetic components has tended to limit the desirability of conventional coupled inductor type boost DC to DC converters for certain applications, e.g. spacecraft power systems.
Thus, there is a need in the art for a small, light weight, low cost improved coupled inductor type boost DC to DC converter design capable of performing the functions of energy storage, power switch drive, input current ripple cancellation and regulated low voltage supply generation.